Below is a comparison of the protocols for recording electrocardiograms in awake mice. On the left is a partial description of the steps involved if using telemetric implants. On the right are the steps involved if using the ECGenie.

Species: Adult mic

Step Telemetric Implants 1,2 Step ECGenie 1,3,4
1. Remove fur from the surgical incision sites (Nair) and clean the exposed skin with Betadine followed by 70% alcohol. 1. Gently place the mice on the ECGenie platform & allow them to acclimate for ~ 10 min.
1. Anesthetize and place the mouse in the supine position, then make a ~ 1cm midscapular transverse incision on the back of the mouse. 5
2. Using round tip scissors, undermine theskin on the left lower back to create a subcutaneous pocket large enough to implant the transmitter.
3. Insert the transmitter device into the pocket with the side of the device containingthe predrilled suture holes facing up; fix it to the overlying skin with 5-0 nylon sutures.
4. Close all incisions and openings with nylon sutures with the knots buried beneath the skin.
5. Manage pain via a bolus injection of 0.1 mg/kg of buprenorphine subcutaneously.
6. Return the animal to the cage and allow recovering or up to 3 weeks for it to return to its pre-surgical body weight.
7. Power on the battery in the transmitter using a magnet. Verify the functioning of the transmitter via an AM radio placed close to the device and listen for a high-pitched tone that corresponds to the cardiac cycle.
8. Place the signal reception plate under the animal cage and connect the cables to thedata acquisition system for recording, storage and analysis.
9. Record ECG in Awake Mice 2. Record ECG in Awake Mice

 

References:

 

  1. Ho D et al. Heart Rate and Electrocardiography Monitoring in Mice. Curr Protoc Mouse Biol. 2011 Mar 1;1:123-139.
  2. Georgetown University Animal Care and Use Committee Standard Procedure: Telemetry Unit Implantation in Mice and Rats

http://ora.georgetown.edu/guacuc/pdf/Telemetry_Procedures-6-20-06-1.pdf

  1. Heier et al. Development of electrocardiogram intervals during growth of FVB/N neonate mice. BMC Physiol. 2010 Aug 24;10:16.
  2. Suidan et al. Lack of tryptophan hydroxylase-1 in mice results in gait abnormalities. PLoS One. 2013;8(3):e59032.